Ocean Dynamics

, Volume 65, Issue 7, pp 1029–1036 | Cite as

Freshwater transport in the coupled ocean-atmosphere system: a passive ocean

Article
Part of the following topical collections:
  1. Topical Collection on Atmosphere and Ocean Dynamics: A Scientific Workshop to Celebrate Professor Dr. Richard Greatbatch's 60th Birthday, Liverpool, UK, 10-11 April 2014

Abstract

Conservation of water demands that meridional ocean and atmosphere freshwater transports (FWT) are of equal magnitude but opposite in direction. This suggests that the atmospheric FWT and its associated latent heat (LH) transport could be thought of as a “coupled ocean/atmosphere mode.” But what is the true nature of this coupling? Is the ocean passive or active? Here, we analyze a series of simulations with a coupled ocean-atmosphere-sea ice model employing highly idealized geometries but with markedly different coupled climates and patterns of ocean circulation. Exploiting streamfunctions in specific humidity coordinates for the atmosphere and salt coordinates for the ocean to represent FWT in their respective medium, we find that atmospheric FWT/LH transport is essentially independent of the ocean state. Ocean circulation and salinity distribution adjust to achieve a return freshwater pathway demanded of them by the atmosphere. So, although ocean and atmosphere FWTs are indeed coupled by mass conservation, the ocean is a passive component acting as a reservoir of freshwater.

Keywords

Freshwater transport Latent heat transport Hydrological cycle 

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Copyright information

© Springer-Verlag Berlin Heidelberg 2015

Authors and Affiliations

  1. 1.Department of MeteorologyUniversity of ReadingReadingUK
  2. 2.Department of Earth Atmosphere and Planetary SciencesMassachusetts Institute of TechnologyCambridgeUSA

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